SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd85914a04deae2fff1e8842616dff243db14c5c50de5a5a231c22d0e8715fbe9' 
  AND token = 'j66zQiimjkl3zTItx6KnkuMuMA7LOYG6Wn4M4Qn6FV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}